Grinding apparatus

Abstract

A grinding apparatus includes a table having a holding surface, a grinding unit grinding a wafer held on the holding surface, a notification portion notifying an operator of information, an imaging unit illuminating a ground surface of the wafer which is held and ground with an illumination and imaging the ground surface, a detecting portion detecting a cross line in an imaged picture, a memory storing an X-axis and Y-axis coordinate position of an intersection point of the cross line detected, a spotlight illuminating the holding surface at the X-axis and Y-axis coordinate position stored, and a controller causing the notification portion to notify the operator that the cross line has been detected and stopping grinding operations of the grinding apparatus.

What is claimed is: 
     
         1 . A grinding apparatus comprising:
 a holding table including a porous plate having a holding surface on which a wafer is held;   holding table rotation means rotating the holding table with a center of the holding table as an axis for rotation;   grinding means grinding the wafer held on the holding surface with grinding stones;   notification means notifying an operator of various kinds of information;   imaging means illuminating a ground surface of the wafer which is held on the holding surface and ground with the grinding stones with an illumination and imaging the ground surface;   detecting means detecting a cross line in a picture imaged by the imaging means;   storage means storing an X-axis and Y-axis coordinate position of an intersection point of the cross line detected by the detecting means;   a spotlight illuminating the holding surface at the X-axis and Y-axis coordinate position stored in the storage means; and   control means causing the notification means to notify the operator that the detecting means has detected the cross line and stopping grinding operations of the grinding apparatus.